High-resolution in vivo binding data show that TBP initiates transcription at TATA promoters with and without TFIID [RNA-seq]

This study investigates how the general transcription factor TFIID binds to different core promoter types in vivo. We performed high-resolution ChIP-nexus for all 14 subunits of the Drosophila TFIID complex (TBP and TAF1 to TAF13), as well as for NC2a, NC2ß, and Mot1, under both DMSO (control) and Triptolide treatments to capture various transcriptional states.The goal of the study was to define TFIID's in vivo architecture and compare its function across promoters. We show that TBP binding is promoter-specific, enabling de novo classification of TATA, DPR, and housekeeping promoters. We provide in vivo evidence for TAF-independent transcription initiation specifically at TATA promoters, which correlates with NC2 binding and offers a mechanistic explanation for their distinct transcriptional bursting properties. Overall design: Total mRNA from Drosophila melanogaster Kc167 cells.